Ductal lavage is an inefficient method of biomarker measurement in high-risk women.

Effective methods of serial epithelial sampling to measure breast-specific biomarkers will aid the rapid evaluation of new preventive interventions. We report here a proof-of-principle phase 2 study to assess the utility of ductal lavage (DL) to measure biomarkers of tamoxifen action. We enrolled women with a 5-year breast cancer risk estimate >1.6% or the unaffected breast of women with T1a or T1b breast cancer. After entry DL, participants chose tamoxifen or observation and underwent repeat DL 6 months later. Samples were processed for cytology and immunohistochemistry for estrogen receptor alpha, Ki-67, and cyclooxygenase-2. Of 182 women recruited, 115 (63%) underwent entry and repeat DL; 85 (47%) had sufficient cells for analysis from > or =1 duct at both time points; in 78 (43%), cells were sufficient from > or =1 matched ducts. Forty-six women chose observation and 39 chose tamoxifen. We observed greater reductions in the tamoxifen group than in the observation group for Ki-67 (adjusted P = 0.03) and estrogen receptor alpha (adjusted P = 0.07), but not in cyclooxygenase-2 (adjusted P = 0.4) labeling. Cytologic findings showed a trend toward improvement in the tamoxifen group compared with the observation group. Interobserver variability for cytologic diagnosis between two observers showed good agreement (kappa = 0.44). Using DL, we observed the expected changes in tamoxifen-related biomarkers; however, poor reproducibility of biomarkers in the observation group, the 53% attrition rate of subjects from recruitment to biomarker analyses, and the expense of DL are significant barriers to the use of this procedure for biomarker assessment over time.

COX-2 and PPARgamma expression are potential markers of recurrence risk in mammary duct carcinoma in-situ.

BACKGROUND: In women with duct carcinoma in-situ (DCIS) receiving breast conservation therapy (BCT), in-breast recurrences are seen in approximately 10%, but cannot be accurately predicted using clinical and histological criteria. We performed a case-control study to identify protein markers of local recurrence risk in DCIS. METHODS: Women treated for DCIS with BCT, who later developed in-breast recurrence (cases) were matched by age and year of treatment to women who remained free of recurrence (controls). RESULTS: A total of 69 women were included in the study, 31 cases and 38 controls. Immunohistochemical evaluation of DCIS tissue arrays was performed for estrogen receptor, progesterone receptor, HER-2/neu, cyclin D1, p53, p21, cycloxygenase-2 (COX-2) and peroxisome proliferator activated receptor gamma (PPARgamma). Two markers were significantly different between cases and controls on univariate analysis: strong COX-2 expression was associated with increased risk of recurrence, with 67% vs. 24% positivity in cases and controls p = 0.006; and nuclear expression of PPARgamma was associated with protection from recurrence with 4% vs. 27% positivity in cases and controls, p = 0.024. In a multivariate model which included size, grade, COX-2 and PPARgamma positivity, we found COX-2 positivity to be a strong independent risk factor for recurrence (OR 7.90, 95% CI 1.72-36.23)., whereas size and grade were of borderline significance. PPARgamma expression continued to demonstrate a protective trend, (OR 0.14, 95% CI 0.06-1.84). CONCLUSION: Our findings suggest that COX-2 and PPARgamma should be investigated further as biologic markers to predict DCIS recurrence, particularly since they are also potential therapeutic targets.

Reproducibility of ductal lavage cytology and cellularity over a six month interval in high risk women.

BACKGROUND: Ductal lavage (DL) allows repeat sampling of breast epithelium for serial observation in a chemoprevention setting; however, the reproducibility of duct cannulation, cell yield and cytology has not been addressed. METHODS: We conducted a Phase 2 trial, wherein high risk women chose tamoxifen treatment or observation following an entry DL procedure. We present data from the non-intervention arm of our study to assess the reproducibility of cannulation, cell yield, and cytologic diagnosis from DL of the same duct at two time-points. Inter-observer variability was assessed by a blinded review of Papanicoloau-stained slides by two cytopathologists. RESULTS: Sixty-five women had a successful lavage of 187 ducts at baseline and chose observation; 63/65 (97%) had a successful lavage 6 months later. Successful recannulation of the same duct was accomplished in 63 women (97%) and162 ducts (87%). Total epithelial cell yields >or=100 were obtained from 57/65 women (88%) and 129/187 ducts (69%) at baseline, and 46/63 women (73%) and 80/162 ducts (49%) at both time-points. Cytologic diagnosis was reproducible in 27/63 (43%) women and 77/162 (48%) ducts. Inter-observer variability for cytologic diagnosis between two observers showed good agreement (kappa = 0.62). CONCLUSIONS: Recannulation and lavage of the same duct after a 6 month interval can be achieved with high frequency; however, reproducibility of cell yield and cytologic findings from the same duct is sub-optimal, leading to significant attrition of evaluable subjects. The utility of DL for the serial monitoring of breast epithelium is therefore limited.